Construction method of tea knowledge graph

The invention provides a construction method of a tea knowledge graph, which can identify named entities in the tea industry, complete ontology construction by means of experience of tea experts, automatically extract unstructured data features in combination with a bidirectional long-short-term memory network and a conditional random field model, improve knowledge extraction efficiency and improve knowledge extraction efficiency. According to the method, knowledge maps of 13 links in the tea production process of tea varieties, tea products, tea tree growth environments, tea tree breeding, tea garden construction, tea garden pruning, fresh leaf picking and the like are constructed, and the construction method comprises the following steps: establishing a tea field knowledge map database; constructing a tea knowledge graph ontology, and defining entities, relationships and attributes of each secondary graph; extracting data, namely extracting the semi-structured data by adopting a web crawler and a data analy